DOC AIRBUS | AMM A320FCONDITIONED SERVICE AIR SYSTEM (CSAS) - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The Conditioned Service Air System (CSAS) is an air temperature conditioning system and is part of the aircraft's Fuel Tank Inerting System (FTIS) (Ref. 470000). The FTIS supplies inert gas into the fuel tanks and this causes all oxygen to flow out of the tanks. This reduces the flammability in the fuel tanks.
The CSAS cools the hot engine bleed air and supplies the conditioned air to the Inert Gas Generation System (IGGS) (Ref. 471100).
The CSAS is installed near the air conditioning pack 1 in the belly fairing on the left hand side of the aircraft.
** ON A/C NOT FOR ALL The Conditioned Service Air System (CSAS) is an air temperature conditioning system and is part of the aircraft's Fuel Tank Inerting System (FTIS) (Ref. 470000). The FTIS supplies inert gas into the fuel tanks and this causes all oxygen to flow out of the tanks. This reduces the flammability in the fuel tanks.
The CSAS cools the hot engine bleed air and supplies the conditioned air to the Inert Gas Generation System (IGGS) (Ref. 471100).
The CSAS is installed near the air conditioning pack 1 in the belly fairing on the left hand side of the aircraft.
2. Component Location
** ON A/C NOT FOR ALL 
CSAS Component Location| FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 100HW | CSAS CONTROL UNIT | 122 | 21-58-34 | ||
| 110HW | MODULE-TEMP CONTROL,CSAS | 191 | 21-58-54 | ||
| 111HW | VALVE-ISOLATION,CSAS | 191 | 21-58-51 | ||
| 113HW | BYPASS VALVE | 191 | 21-58-00 | ||
| 115HW | SENSOR-TEMP DUCT,CSAS | 191 | 21-58-00 | ||
| 117HW | SENSOR-PRESS,CSAS | 191 | 21-58-00 | ||
| 5101HM | OZONE CONVERTER-ASSY,CSAS | 191 | 21-58-42 | ||
| 5103HM | EXCHANGER-HEAT,CSAS | 191 | 21-58-00 | ||
3. System Description
The Conditioned Service Air System (CSAS) operates only during flight conditions and it stops the operation of the system when the aircraft is on ground.
The CSAS controller is the primary computer which controls this system. The controller operates the valves, monitors air temperature and air pressure to supply the necessary flow of conditioned air to the inert gas generation system.
The CSAS gets hot compressed air (bleed air) from the pneumatic air distribution system. This hot bleed air comes from the manifold near the high pressure ground connector and flows through the CSAS isolation valve to an ozone converter. The CSAS isolation valve controls the airflow in the system.
When there is no bleed air pressure or electrical power, the CSAS isolation valve closes automatically and stops the operation of the system.
The hot air flows from the ozone converter through a duct to the Temperature Control Module (TCM), which is installed on the ram air inlet side of the air conditioning pack heat exchanger. The TCM controls the temperature of the air to approximately 60 DEG.C (140.00 DEG.F).
The Temperature Control Module (TCM) has :
** ON A/C NOT FOR ALL The Conditioned Service Air System (CSAS) operates only during flight conditions and it stops the operation of the system when the aircraft is on ground.
The CSAS controller is the primary computer which controls this system. The controller operates the valves, monitors air temperature and air pressure to supply the necessary flow of conditioned air to the inert gas generation system.
The CSAS gets hot compressed air (bleed air) from the pneumatic air distribution system. This hot bleed air comes from the manifold near the high pressure ground connector and flows through the CSAS isolation valve to an ozone converter. The CSAS isolation valve controls the airflow in the system.
When there is no bleed air pressure or electrical power, the CSAS isolation valve closes automatically and stops the operation of the system.
The hot air flows from the ozone converter through a duct to the Temperature Control Module (TCM), which is installed on the ram air inlet side of the air conditioning pack heat exchanger. The TCM controls the temperature of the air to approximately 60 DEG.C (140.00 DEG.F).
The Temperature Control Module (TCM) has :
- A CSAS heat exchanger,
- A hot air bypass valve,
- A temperature sensor,
- A pressure sensor.
The CSAS heat exchanger is installed in the ram air channel. The heat exchanger decreases the temperature of the hot bleed air.
To get conditioned and temperature controlled air, some of the hot air is tapped upstream of the heat exchanger and bypasses the heat exchanger through a duct. A hot air bypass valve is installed in the bypass duct. The hot air bypass valve adds hot bleed air to the always cold air downstream of the heat exchanger to increase the temperature.
A temperature sensor and a pressure sensor, which are installed in the duct to the Inert Gas Generation System (IGGS), monitor the conditioned air and transmit the signals to the CSAS controller.
The CSAS controller receives the data, compares it to the demand from the IGGS controller and, if necessary, operates the valves.
4. Power Supply
The electrical power for the Conditioned Service Air System (CSAS) comes from the DC1 power supply bus (28VDC).
The CSAS controller 100HW operates the CSAS isolation valve 111HW and the hot air bypass valve 113HW and receives discrete position feedback signals from both valves. The CSAS controller receives analogue signals from the temperature sensor 115HW and from the pressure sensor 117HW.
The electrical layout is shown in aircraft schematic manual (Ref. ASM 215300).
** ON A/C NOT FOR ALL The electrical power for the Conditioned Service Air System (CSAS) comes from the DC1 power supply bus (28VDC).
The CSAS controller 100HW operates the CSAS isolation valve 111HW and the hot air bypass valve 113HW and receives discrete position feedback signals from both valves. The CSAS controller receives analogue signals from the temperature sensor 115HW and from the pressure sensor 117HW.
The electrical layout is shown in aircraft schematic manual (Ref. ASM 215300).
5. Interface
The Conditioned Service Air System (CSAS) has interfaces with:
The Conditioned Service Air System (CSAS) has interfaces with:
A. The Inert Gas Generation System (IGGS)
The CSAS controller is connected to the IGGS controller through an ARINC 429 bus. The two controllers monitor the operational conditions independently. The CSAS controller receives temperature information from the IGGS.
The CSAS controller is connected to the IGGS controller through an ARINC 429 bus. The two controllers monitor the operational conditions independently. The CSAS controller receives temperature information from the IGGS.
B. The Pneumatic Air Distribution System (PADS)
The CSAS tapping point for the PADS is is near the high pressure ground connector in the belly fairing. The CSAS gets bleed air from the engines, APU or high pressure ground supply.
The CSAS tapping point for the PADS is is near the high pressure ground connector in the belly fairing. The CSAS gets bleed air from the engines, APU or high pressure ground supply.
C. The Flight Warning System (FWS)
The CSAS controller is the only interface of the Fuel Tank Inerting System (FTIS) to the FWS to the Flight Warning Computers (FWCs). There is only one ECAM message indication in the cockpit.
The CSAS controller is the only interface of the Fuel Tank Inerting System (FTIS) to the FWS to the Flight Warning Computers (FWCs). There is only one ECAM message indication in the cockpit.
D. The Centralized Fault and Display System (CFDS)
The Built-In Test Equipment (BITE) application of the CSAS controller is the interface to the CFDS through the Centralized Fault Display Interface Unit (CFDIU).
The CFDIU gives test function in the interactive test mode.
You can do different CSAS tests in interactive mode.
The Built-In Test Equipment (BITE) application of the CSAS controller is the interface to the CFDS through the Centralized Fault Display Interface Unit (CFDIU).
The CFDIU gives test function in the interactive test mode.
You can do different CSAS tests in interactive mode.
E. System Data Acquisition Concentrator (SDAC)
The system data acquisition concentrator receives different types of electrical signals and parameters from other aircraft systems. The SDAC changes these signals into a digital format (ARINC 429 standard) and supplies them to the CSAS controller.
The system data acquisition concentrator receives different types of electrical signals and parameters from other aircraft systems. The SDAC changes these signals into a digital format (ARINC 429 standard) and supplies them to the CSAS controller.
6. Component Description
A. CSAS Controller FIN: 100-HW
The CSAS controller is installed in rack 92VU of the avionics bay in the pressurized area. It is a single lane digital controller with an analogue safety shut-off (hardware monitor channel). It controls and monitors the CSAS and has BITE functions for the inert gas generation system.
It has input and output connectors for:
The CSAS controller is installed in rack 92VU of the avionics bay in the pressurized area. It is a single lane digital controller with an analogue safety shut-off (hardware monitor channel). It controls and monitors the CSAS and has BITE functions for the inert gas generation system.
It has input and output connectors for:
- The ARINC 429 bus system,
- The RS232 serial interface,
- The discrete signals,
- The analogue signals,
- The power supply.
B. CSAS Isolation Valve (111HW)
The CSAS isolation valve is a solenoid controlled, pneumatically actuated butterfly valve.
The CSAS isolation valve let hot bleed air flow to the Temperature Control Module (TCM).
Without bleed air pressure or without electrical power the valve closes automatically and stops the operation of the system.
The CSAS controller operates the isolation valve.
The CSAS isolation valve is a solenoid controlled, pneumatically actuated butterfly valve.
The CSAS isolation valve let hot bleed air flow to the Temperature Control Module (TCM).
Without bleed air pressure or without electrical power the valve closes automatically and stops the operation of the system.
The CSAS controller operates the isolation valve.
C. Ozone Converter (5101HM)
The ozone converter catalytically decreases the ozone concentration of the bleed air which flows to the TCM. The decreased ozone concentration prevents damage to the air separation module fibers of the inert gas generation system. The ozone converter is installed downstream of the isolation valve.
The ozone converter catalytically decreases the ozone concentration of the bleed air which flows to the TCM. The decreased ozone concentration prevents damage to the air separation module fibers of the inert gas generation system. The ozone converter is installed downstream of the isolation valve.
D. Temperature Control Module (110HW)
The Temperature Control Module (TCM) has:
The Temperature Control Module (TCM) has:
- a CSAS heat exchanger,
- a hot air bypass valve,
- a temperature sensor,
- a pressure sensor.
(1) CSAS Heat Exchanger (5103HM)
The CSAS heat exchanger is installed in the ram air channel upstream of the pack heat exchanger. The ram air from outside the aircraft flows through the heat exchanger and cools the heat exchanger fins. The heat exchanger decreases the temperature of the hot bleed air from the pneumatic system.
The CSAS heat exchanger is installed in the ram air channel upstream of the pack heat exchanger. The ram air from outside the aircraft flows through the heat exchanger and cools the heat exchanger fins. The heat exchanger decreases the temperature of the hot bleed air from the pneumatic system.
(2) Hot Air Bypass Valve (113HW)
The hot air bypass valve is installed in the hot air bypass duct. The bypass valve adds hot bleed air to the cold air from the heat exchanger to increase the temperature.
The hot air bypass valve has an actuator with a stepper motor, which moves a butterfly valve between its open and its closed position.
The CSAS controller operates the hot air bypass valve.
The hot air bypass valve is installed in the hot air bypass duct. The bypass valve adds hot bleed air to the cold air from the heat exchanger to increase the temperature.
The hot air bypass valve has an actuator with a stepper motor, which moves a butterfly valve between its open and its closed position.
The CSAS controller operates the hot air bypass valve.
(3) Temperature Sensor (115HW)
A temperature sensor monitors the temperature of the conditioned air in the duct when it flows to the inert gas generation system.
The dual element temperature sensor transmits this data to the CSAS controller.
A temperature sensor monitors the temperature of the conditioned air in the duct when it flows to the inert gas generation system.
The dual element temperature sensor transmits this data to the CSAS controller.
(4) CSAS Outlet Pressure Sensor (117HW)
A pressure sensor monitors the pressure of the conditioned air in the duct when it flows to the inert gas generation system.
The pressure sensor is installed between the temperature sensor and the inlet of the inert gas generation system. This sensor senses pressure conditions in the system and transmits this data to the CSAS controller.
A pressure sensor monitors the pressure of the conditioned air in the duct when it flows to the inert gas generation system.
The pressure sensor is installed between the temperature sensor and the inlet of the inert gas generation system. This sensor senses pressure conditions in the system and transmits this data to the CSAS controller.
7. Operation/Control and Indicating
A. Correct Operation
The CSAS operates only during flight conditions. The system status is automatically set to on.
The system operates when:
The CSAS operates only during flight conditions. The system status is automatically set to on.
The system operates when:
- bleed air from engine 1, or engine 2 bleed air and cross bleed valve open
- electrical power is available
- air conditioning pack 1 operates, or pack 2 and cross bleed valve open.
B. Operation when a failure occurs
The CSAS does not operate if the bleed air pressure is too low.
If the CSAS detects a failure, the CSAS controller sends a warning to the FWC. A failure message will be displayed in the cockpit in flight phases 1 and 10 for maintenance functions.
The CSAS does not operate if the bleed air pressure is too low.
If the CSAS detects a failure, the CSAS controller sends a warning to the FWC. A failure message will be displayed in the cockpit in flight phases 1 and 10 for maintenance functions.
8. BITE Test
The CSAS application is a software, which is hosted in the CSAS controller. The CSAS application has an operation partition and a Built-In Test Equipment partition (BITE). The CSAS BITE also has a part of the BITE function of the Inert Gas Generation System (IGGS).
The CSAS BITE analyzes the test results from the operational software and from the IGGS controller to identify a defective component.
The CSAS BITE transmits failure messages (troubleshooting data) to the Centralized Fault Display System (CFDS) and covers the equipment for conditioned service air system and inert gas generation system.
The CSAS BITE provides an interactive mode for tests and specific functions.
The CSAS application is a software, which is hosted in the CSAS controller. The CSAS application has an operation partition and a Built-In Test Equipment partition (BITE). The CSAS BITE also has a part of the BITE function of the Inert Gas Generation System (IGGS).
The CSAS BITE analyzes the test results from the operational software and from the IGGS controller to identify a defective component.
The CSAS BITE transmits failure messages (troubleshooting data) to the Centralized Fault Display System (CFDS) and covers the equipment for conditioned service air system and inert gas generation system.
The CSAS BITE provides an interactive mode for tests and specific functions.
A. Normal Mode
The CSAS BITE report system status of CSAS and IGGS and all related fault messages continuously to the Centralized Fault Display Interface Unit (CFDIU).
In normal mode the CSAS BITE does not affect the operation of the systems.
The CSAS BITE report system status of CSAS and IGGS and all related fault messages continuously to the Centralized Fault Display Interface Unit (CFDIU).
In normal mode the CSAS BITE does not affect the operation of the systems.
B. Interactive Mode
The CSAS BITE is the interface to the Centralized Fault Display Interface Unit (CFDIU) and gives access to the test function. The interactive mode test is available only during ground operation. The operator can manually start the test from the System/Test page on the Multipurpose Control and Display Unit (MCDU).
The CSAS BITE is the interface to the Centralized Fault Display Interface Unit (CFDIU) and gives access to the test function. The interactive mode test is available only during ground operation. The operator can manually start the test from the System/Test page on the Multipurpose Control and Display Unit (MCDU).
(1) System Test without bleed air
This test checks the electrical connections and gives information about the system status.
This test has the following functions:
This test checks the electrical connections and gives information about the system status.
This test has the following functions:
- The CSAS controller and its application
- The IGGS controller and its application
- The sensors
- The valve position
- The wiring
- The external/internal communication.
(2) System Test with bleed air
This test checks the components and gives information about the system status.
This test has the following functions:
This test checks the components and gives information about the system status.
This test has the following functions:
- The CSAS controller and its application
- The IGGS controller and its application
- The sensors
- The valves
- The wiring
- The external/internal communication
- The functionality of the components.